1. Field of Invention
This invention relates to the field of hearing testing and analysis. More specifically, the invention comprises a hardware and software system for automatically calibrating the audio output level of a personal computer used to evaluate human hearing. The requirement of hardware in the loop has the added benefit of rendering unauthorized copies of the software unusable.
2. Description of Prior Art
Audio testing equipment has long been used to diagnose human hearing problems. Recent advances, particularly with the advent of computer controls, have allowed the diagnosis of many conditions beyond simple hearing loss. Hypersensitivity to sound is a major symptom in the diagnosis of disorders such as central auditory processing dysfunction (CAPD), attention deficit hyperactivity dysfunction (ADHD), attention deficit disorder (ADD), pervasive development dysfunction (PDD), dyslexia, autism, and others. The testing equipment must be accurately calibrated so that the sound pressure produced for the test corresponds to known levels used in other testing.
Hearing testing has traditionally been performed by audio technologists. However, modern personal computers have made it possible for testing to be conducted by non-professionals. Many personal computers now have sophisticated audio input and output capabilities (xe2x80x9csound cardsxe2x80x9d). With the proper software, these computers are capable of conducting relatively sophisticated tests. However, running the same software on different computers will result in a variety of sound output levels. This disparity results from the fact that the different computers have different sound cards, different speakers, etc. In order for diagnostic software to be run on a variety of computers, it is therefore necessary to provide a universal calibrating technique.
The known devices for administering sophisticated hearing tests are therefore limited in that they:
1. Require the use of specifically designed and calibrated testing equipment;
2. Can only be run by an audio technologist; or
3. In the case of software-based systems, do not provide for calibration of the personal computer audio output in order to comply with known sound levels.
Accordingly, several objects and advantages of the present invention are:
1. To provide a system which can be run on commonly available personal computers;
2. To provide a system which can be run by a person having no specialized training as an audio technician;
3. To provide a system which can automatically calibrate the sound output level for virtually any personal computer;
4. To provide a system which is relatively inexpensive; and
5. To provide a system which requires hardware in the loop, thereby rendering unauthorized copies of the software unusable.